There and Back Again
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去而复返 (There and Back Again) (zhs)

Enchantment - Saga (CMC 5)
(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I -- Up to one target creature can't block for as long as you control There and Back Again. The Ring tempts you.
II -- Search your library for a Mountain card, put it onto the battlefield, then shuffle.
III -- Create Smaug, a legendary 6/6 red Dragon creature token with flying, haste, and "When this creature dies, create fourteen Treasure tokens."